81608528 has 20 divisors (see below), whose sum is σ = 158258100. Its totient is φ = 40767744.

The previous prime is 81608521. The next prime is 81608561. The reversal of 81608528 is 82580618.

It can be written as a sum of positive squares in 2 ways, for example, as 74166544 + 7441984 = 8612^2 + 2728^2 .

It is a junction number, because it is equal to n+sod(n) for n = 81608491 and 81608500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81608521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29876 + ... + 32492.

It is an arithmetic number, because the mean of its divisors is an integer number (7912905).

Almost surely, 2^81608528 is an apocalyptic number.

It is an amenable number.

81608528 is a deficient number, since it is larger than the sum of its proper divisors (76649572).

81608528 is a wasteful number, since it uses less digits than its factorization.

81608528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4574 (or 4568 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 38.

The square root of 81608528 is about 9033.7438529106. The cubic root of 81608528 is about 433.7556865712.

The spelling of 81608528 in words is "eighty-one million, six hundred eight thousand, five hundred twenty-eight".